Power Steering Question

A few years back, I helped my dad build a 55 F100. He used a Cordoba frame and a Mustang II suspension. I believe he also used a Chrysler power steering pump. The truck drives well, but the steering is extremely quick. My dad said he remembers reading about a company that modified the power steering pumps, either with different gears or just different pressure, so that the steering wouldn't be so quick. He wants the truck to have a little heavier steering.